Semakau Island is situated south of the Singapore main island. It is primarily used as a landfill for the slag and ashes from four waste incineration plants on the main island. In preparation for the construction of the landfill, using brought-in soil, two islands were merged after which a large “bund” was built to contain the slag and ashes which are collected at one common point, at Tuas, from where they are barged to the Semakau Island Landfill to be subsequently dispersed.

The landfill itself is operated by the National Environmental Agency, NEA, which is part of the Singapore Ministry of Energy and Water Resources, MEWR. At the present time, the main activities on the island are those of NEA related to the operation of the landfill.

The main development, test and demonstration site for REIDS is a 6.4 ha plot, designated as P2, on Semakau Island.

The REIDS implementation of the research, demonstration and test bed on Semakau Island is articulated around two distinct areas on the island: